Simulating the influences of bat curtailment on power production at wind energy facilities

The development and expansion of wind energy is considered a key threat to bat populations in North America and globally. Several approaches to mitigating the impacts of wind energy development on bat populations have been developed, including curtailing wind turbine operation at night during lower wind speeds when bats are thought to be more active. Blanket curtailment approaches have shown substantial promise in reducing bat fatalities at wind energy facilities, but they also reduce the amount of energy extracted from the wind by turbines. A related approach, referred to as smart curtailment, uses bat activity and other variables to predict when bats will be at the greatest risk at a given wind facility. In some contexts, a smart curtailment approach might reduce bat fatalities while also reducing energy loss relative to blanket curtailment. However, it has not been clear how to compare blanket curtailment and smart curtailment approaches in terms of annual energy production at wind facilities. Here, we describe a new approach to simulating the influence of blanket and smart curtailment approaches on energy production at wind energy facilities, and demonstrate the approach using 6 wind energy development areas in the Canadian province of Alberta. We show how stakeholders involved can explore the potential influences of various kinds of bat activity on energy production. We present the results of our Alberta analysis and conclude with some caveats and recommendations for future work on simulating the influences of bat curtailment on energy production at wind energy facilities.